Double-hung window assemblies having pivotal sashes are well known in the art. Typically each of the sashes includes a pair of opposing pivot pins which outwardly extend into respective rotatable members in the side jambs. The rotatable members are each coupled to a sash balance assembly which provides an upward force to counteract, and thus balance, the gravitational force of the particular sash.
When pivoting the window, the center of gravity of the window is moved out of line with the force of the sash balance assembly, which can cause the sash balance assemblies to force the sash up. To counteract this force, the rotatable member often includes a rotatable brake assembly which locks the sash balance when the sash is pivoted. The brake assembly is typically actuated by rotation of the pivot pin when the sash is pivoted. Occasionally, the brake assembly jams and fails to rotate upon rotation of the pivot pin. When this happens, the pivot pin can twist and potentially break causing a catastrophic failure. Specifically, if the pivot pin breaks the sash can potentially fall out of the window frame.
The present invention is provided to solve this and other problems.